Analysis of nuclear and mitochondrial genes in patients with pseudoexfoliation glaucoma

Abstract

Purpose

Pseudoexfoliation glaucoma (PEG) is the most prevalent secondary open angle glaucoma occurring worldwide. The search for a genetic cause in PEG has been largely unsuccessful despite evidence of hereditary transmission.

Methods

The nuclear genes MYOC, OPTN, WDR36, CYP1B1, OPA1, and OPA3 were sequenced in patients with PEG. The entire mitochondrial DNA (mtDNA) coding region was also sequenced, relative mtDNA content was investigated, and mitochondrial respiration was assessed.

Results

No novel or previously reported mutations were present in the nuclear genes MYOC, OPTN, CYP1B1, WDR36, OPA1, or OPA3 in 29 PEG patients. Twenty-six patients (89.7%) had no pathological or potentially pathological mtDNA mutation(s); however, three patients (10.3%) had potentially pathologic mtDNA nucleotide changes not found in controls. PEG patients did not differ significantly from controls in relative mitochondrial content (p=0.98) or in mitochondrial respiratory activity (p=0.18).

Conclusions

These PEG patients had no mutations in nuclear genes associated with other types of glaucoma or other inherited optic neuropathies, and there was little evidence of mitochondrial abnormalities. These results imply that the nuclear genes and mitochondrial parameters evaluated here are less important determinants of PEG than other factors related to the presence of pseudoexfoliation material.